<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <script src="../react18/react.development.js"></script>
    <script src="../react18/react-dom.development.js"></script>
    <script src="../react18/babel.min.js"></script>
</head>
<body>
    <div id="app"></div>
    <script type="text/babel">
        class App extends React.Component{
            render(){
                return <form action="">
                    <p>
                        请输入用户名
                        <input type="text" ref="username"/>
                        </p>
                        <p>
                            请输入密码
                            <input type="text" ref="password"/>
                            </p>
                            <button onClick={this.formSubmit}>提交</button>
                    </form>
            }

        formSubmit=(e)=>{
            e.preventDefault();
            // console.log(e);
            console.log(this);
            console.log(this.refs.username.value);
            console.log(this.refs.password.value);
        }
        }
        ReactDOM.createRoot(document.getElementById("app")).render(<App />)
    </script>
</body>
</html>